In ventilation duct systems, there are oftentimes a variety of components connected to the duct system that must be periodically inspected, maintained, and repaired, as necessary. Due to their internal construction, however, these components are typically not easily accessible for routine inspection, maintenance, and repair.
One such internal device is a damper. As is known, a damper includes one or more movable plates, blades, or curtains that control the flow of a fluid, usually air, in the duct system. Like many mechanical devices, dampers require preventive maintenance and, in the event of operational failure, replacement or repair. As one particular example, fire dampers are safety devices that are often found in walls or floors of a building and are designed to prevent the rapid spread of flames and hot gases through the building via the ventilation duct system. Fire dampers include a fusible link that, when exposed to excessive heat, causes the damper to abruptly close. The action closes the duct system so that it does not provide an avenue for the spread of fire through the building.
Because some dampers, such as fire dampers, are safety devices, they must be protected from collateral damage to the ductwork so that they maintain their operational effectiveness in the event of an emergency. For example, because fire dampers are designed to prevent the spread of fire through the ductwork in a building, the ductwork operatively coupled to the damper is designed to break away without damage to the damper itself. In this manner, should part of the building collapse adjacent the damper and dislodge or destroy the ductwork leading up to the damper, the ductwork may cleanly separate from the damper so that the integrity of the damper is maintained. Thus, structural failures that are typically associated with a fire may not defeat the purpose of the damper and thereby cause catastrophic or rampant spread of fire through the ductwork.
Normally, access to the fire damper and the link are provided by a small access door in the duct that is located in proximity to the damper. However, these doors, due to their location and orientation on the ductwork and/or proximity to other components of the duct system or other structures in the building, often provide only limited visibility of the fire damper and link and thus make inspection, maintenance, and repair awkward and difficult. In addition, replacement of the damper and/or the link is often not possible via the access door so that their replacement is a time-consuming and expensive endeavor. Often, replacement in this situation may essentially require dismantling of a large portion of the duct system simply to gain physical access to the fire damper.
Thus, there is a need for improved access to dampers that overcome these and other shortcomings and drawbacks of known access doors and breakaway in ventilation duct systems.